This section provides background information related to the present disclosure which is not necessarily prior art.
The present disclosure relates to a stator core of a rotor. Generally, a stator core used for a motor is provided with a cylindrical core member of metallic material, and is protrusively formed at an inner circumferential surface with a plurality of teeth wound with a coil.
Recently, concomitant with miniaturization of a motor, and in response to a need for miniaturizing and reducing the stator core in weight, a conventional one-bodied stator core is sidelined and a stator core formed by stacking thin metal plates at a predetermined thickness has surfaced, or a cylindrical stator core is frequently favored by assembling split cores each having an approximate ‘T’ shape and a tooth.
However, there is a cumbersome problem in stacking the stator cores in that a plurality of metal plate sheets is performed with a press work each in a same shape, and the each plate sheet must be stacked in a separate process. Another problem of forming the cylindrical stator core through press-fitting of each split core is that an adhesive must be separately used or complementary shapes must be provided to fill up an air gap at each coupled area of the split cores after assembly, in the process of forming the split cores by molding or sintering each split core, and assembling each split core for a cylindrical stator core.
Recently, in order to solve the aforementioned problems, a plurality of unit cores is stacked, the stacked unit cores are simultaneously bent, one or more stacked unit cores that have passed the bending process is coupled to form a ring-shaped stator core, the technique of which is disclosed in a Korean Laid-Open Patent No. 2008-0078944 (Opened on Aug. 29, 2011).
However, the disclosure has a high probability of developing a product defect caused by disengagement in core coupling in the course of coupling of the stator cores that have passed the bending process, and another problem may be generated of reducing a motor efficiency or developing a performance deficiency if the coupled parts are not tightly secured.
It is, therefore, desirable to overcome the above problems and others by providing an improved stator core for a motor.